E-Mail sending to Offcie/Microsoft365 customers not possible - 451 4.7.500 Server busy

Koes 350 Reputation points
2023-10-11T10:38:11.0866667+00:00

Hi,

since this morning 5 am we are not able to send E-mails to office365/Microsoft365 Customers. Our Mails are stuck in our own queue and get the response: host customername.mail.protection.outlook.com 451 4.7.500 Server busy please try again later wit 193.228.149.133 S77719

Can someone check, why we are on an throtteling list with our E-MailServer and remove please?

Microsoft Exchange Online Management
Microsoft Exchange Online Management
Microsoft Exchange Online: A Microsoft email and calendaring hosted service.Management: The act or process of organizing, handling, directing or controlling something.
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  1. Florian Sager 0 Reputation points
    2023-10-11T12:41:32.9233333+00:00

    In the meantime, we're manually adding reported affected IP addresses to an allowed list to provide immediate relief.

    @outlook.com , please allow these two affected IPs to your whitelist:

    116.202.101.96
    78.46.137.249


  2. Alboini Daniele 0 Reputation points
    2023-10-11T12:50:43.8733333+00:00

    Same problem in Italy:

    62.149.169.186


  3. MG 0 Reputation points
    2023-10-11T12:55:17.5033333+00:00

    Hosting France OVH

    151.80.162.141


  4. Rialto Gigante 0 Reputation points
    2023-10-11T12:59:56.44+00:00

    Same problem in Italy:

    Name:   mx1.ilgigante.net

    Address: 213.26.20.177

    0 comments No comments

  5. Leyland Chui 0 Reputation points
    2023-10-11T13:02:13.78+00:00

    Dear @Outlook.com Team

    Same problem in Hong Kong,

    Hosting Hong Kong

    IP : 65.181.73.16

    DNS Reverse Address : mx01.bscnet.com.hk

    Please add IP : 65.181.73.16 to whitelist. Thanks.


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